Packing for rotating shafts



C. A. PARSONS, S. S. COOK AND I M. DOUGLAS.

PACKING FOR ROTATING SHAFTS.

APPLICATION FILED JUNE 1-9, 1918.

Patented Feb. 24, 1920.

In venture.

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7. Db ug/Z v C. A. PARSONS, S. S. COOK AND L. M. DOUGLAS. PACKING FORROTATING SHAFTS.

APPLICATION FILED .IU 1,331,522.

' m8. Patented Feb. 24,1920.

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\Yg O mw V DD Jtanl C. A. PARSONS, S. S. COOK AND L. M. DOUGLAS. PACKINGFOR ROTATING SHAFTS.

FILED JUNEI axles Paraon. anley .6. Cook, 9

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UNITED STATES PATENT OFFICE.

CHARLES ALGERNON PARSONS, 0F NEWCASTLE-UPON-TYN E, AND STANLEY SMITHCOOK AND LOUIS MORTIMER DOUGLAS, OF WALLSEND, ENGLAND; SAID COOK ANDSAID DOUGLAS ASSIG-NORS T0 SAID PARSONS.

PACKING FOR ROTATING SHAFTS.

Application filed June 19,

certain new and useful Improvements in Packing for Rotating Shafts, ofwhich the following is a specification.

The present invention relates to glands for packing rotating shafts andhas for its object to construct such glands in an improved manner sothat leakage along the shaft is minimized while undue wear by running ofthe shaft is avoided.

'Heretofore carbon or like glands for packing rotating shafts have beenemployed consistlng of a series of single rlngs of carbon containedinseparate grooves, and in some cases two rings in a slngle groove havebeen employed. These rings are. usually composed of several segmentswith either plain butt joints or scarfed joints held to the shaft bymeans of an encircling spiral spring, the joints being left slightlyopen to insure that the spring presses the carbons into contact with theshaft. g

In such glands it is necessary to leave a fairly large clearance betweenthe shaft and theinwardly projecting metallic flanges of the gland whichform the partitions between the grooves, this clearance being necessary,as contact betweenthe gland and the shaft when the latter is rotating athigh speeds would have serious consequences.

In such construction it will be seen that the steam can escape throughthat part of the open joint between two segments of the carbon ringwhich is opposite to the radial clearance in the gland partition, thispart ofthe joint not being covered by the partition Walls.

It has also been proposed to pack reciproeating parts such as pistonrods "by metallic rings, two or more rings being placed in a singlegroove and so arranged that one ring Specification of Letters Patent.

.only one direction, while Patented Feb. 24, 1920.

1918. Serial No. 240,886. I V

fits close to the reciprocating rod and has open joints while anotherring in the same groove is undivided and gives a clearance around thereciprocating rod. Y

The present invention consists in a gland having two or more carbon orlike packing rings in each groove, one of the rings having the usualopen joints, while another has closed joints held closely together bymeans of the spring.

The invention further consists in the imi proved carbon glands forpacking rotating shafts hereinafter described.

Referring to the accompanying draw ings:-

Figure 1 is a section of a carbon gland in accordance with theinvention.

Fig. 2 is a section on the line X-X, Fig. 1.

Fig. 3 is a section showing a gland suitable for use where a steam fiowmay be required to be reversed. I

Fig. 4 is a section showing another form of the invention where thesteam flow is in Fig. 5 is a section on the line YY, Fig. 4.

Fig. 6 is a section showing a modified method of holding the carbonsegments.

In the form ofthe invention illustrated in Figs. 1 and 2, the gland a isprovided with three grooves b, b, 6, each groove being slightly widerthan the width required for the carbon packing rings 0, d. A fairlylarge clearance isleft between the shaft e and the inwardly projectingmetallic flanges 7, f, on the gland a. The carbon ring 0 on the steamside in each groove has the usual open joints 9 and is pressed on theshaft by the spring 70, while the segments of the other carbon ring (Zin each groove have closed joints it, the ends of the segments beingheld close against each other by means of the spring Z thereby forming aclosed ring.

There may be a clearance between the bore joints between the segmentsare closed. The

tworings 0, (Z, are arranged so that their joints-g, h are not oppositeeach other so that the second rings almost completely cover the openjoints of the rings on the steam side, so that leakage is reduced to avery small amount.

Stops are usually provided to prevent the carbon rings from rotatingwith the shafts, and in the case of the ring a with the open joints thisstop m is preferably provided at v the top of the gland. The effect ofthis is that with either direction of rotation of the shaft, on accountof the friction between the carbon segments and the shaft, theaccumulated opening of all the joints occurs at the top, adjacent to thestop. Should the closed joint ring be large in the bore due to wear orother cause, its weight will cause it to ride upon the shaftat the top,and the opening of the joints of the other ring being also. on top, thisopening will be most effectively blanked.

In some cases glands are employed in which it is desired to preventfluidfromescaping sometimes in one direction and sometimes-in the oppositedirection, and in such cases two oppositely arranged pairs of rings maybe employed, each pair being situated in a separate groove, or, as shownat Fig. 3, three rings may be employed in one groove, the center ring11. being constructed with open joints and the other two 0', o, withclosed joints. The joints at the segments of the rings may be scarfed,dovetailed or made in any desired form, but preferably plain radialbutts are employed.

' In Fig. 3 there is also illustrated circumferential grooves 12, p, onthe jointing faces for the purpose of assisting in the prevention ofleakage by utilizing the'labyrinth principle.

In the form of the invention shownin Figs; 4; and 5, grooves are cut inring p on the steam side to relieve the inward radial steam pressure andthus reduce the total inward radial force on the carbons, thusdiminishing total friction while retaining a robust form of ring. Theopen ring is prevented from rotation by the pin 7' engaging with theclosed ring 8 which is held to the inwardly projecting flange f on thegland by the pin t. In this case the open ring is held by a bolted ringu instead of by a spring.

' Fig. 6 shows a further method of holding the rings comprising boltedstraps o, a, combined with a spiral spring w.

In addition to reducing the leakage, packing glands constructedaccording to-the invention have the further advantage that it is notnecessary to work with very fine clearances to keepthe leakage withinreasonable limits. Further, a softer quality of carbon can be employedwith larger openings'of the joints of theirings on the steam side toallow for taking up the wear. The tendency of the carbon rings to weargrooves in the shaft is thus avoided.

In order to reduce the liability to leakage across the transverse facesof the carbon rings and partition Walls, the partition wall on the highpressure side may have an increased bore so as to increase the area onwhich the high pressure steam acts. This pressure keeps the adjacentfaces of the rings in close contact. 7

Having now described our invention, what we claim as new and desire tosecure by Letters Patent is 1. In combination with a rotatable shaft, apacking gland having two or more packing rings of carbon or likematerial, the ring at the low pressure end being divided into two ormore pieces without openings at the divisions, the adjacent ring beingdivided into two or more pieces each of which abuts the rotatable shaftbut is circumferentially clear of the adjacent pieces of the same ring,thereby to be affected only individually by transverse vibrations of therotary shaft, and means to hold the pieces of each ring in properposition, both of said rings having a clearance between their outerperipheries and the wall of the gland, substantially as described.

2. In combination with'a rotary shaft, apacking gland, two or morepacking rings of carbon or like material in said gland adjacent eachother, each of said rings being formed of unconnected segments and bothcapable of floating in a direction transverse to their axis, thesegments of one ring. bearing on the shaft but spaced apart from eachother, while the segments of the other ring abut each other but normallyhave a slight clearance between them and the shaft, and means forholding the segments of the rings in proper position, substantially asde-- scribed.

3. In combination with a rotating shaft, a packing gland, two or morepacking rings therein adjacent each other and having clearance betweentheir outer peripheries and the wall of the gland, the ring at the lowpressure end being formed in spaced apart segments and bearing on theshaft, and the other ring being formed in segments abutting each other,and having slight clearance between-themselves"andthe shaft, and.

means for holding therings in proper relation, substantially asdescribed. 4

In testimony whereof we have signed our names to this specification.

CHARLES ALGERNON PARSONS. I STANLEY SMITH 000K.

LOUIS MORTIMER DOUGLAS.

